Molekula
p-Toluenesulfonic acid
Supplying 4,500+ customers in over 80 countries
ISO 9001:2015 & ISO 14001:2015 certified · Supplying laboratories and industry since 1999 · Listed pack sizes are a starting point — we manufacture, source and repack to the quantity you need
p-Toluenesulfonic acid is a strong organic sulfonic acid used as a catalyst in organic synthesis, a pH regulator in pharmaceuticals, and an electrolyte in batteries. It appears as a white crystalline solid with high solubility in water and organic solvents. CAS 104-15-4, molecular formula CH₃C₆H₄SO₃H, molecular weight 172.20 g/mol. Store at ambient conditions. Signal word: Danger (corrosive, harmful if swallowed, may cause respiratory irritation). Molekula supplies p-Toluenesulfonic acid from research to bulk quantities with full documentation and ISO 9001:2015 traceability.
Example image for illustration only. Other packaging and pack sizes are available.
Pricing & pack sizes
In stock — same-day dispatch
These pack sizes aren't a limit. Molekula manufactures, sources and repacks to order — if you need 500 kg and only see 1 kg listed, . We quote from grams to multi-tonne.
Need a different size? Add the nearest pack and change the size in your basket — we price it at the same rate per unit.
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1 kg — £52.00 per pack ex VAT · £62.40 inc. VAT
Need a different quantity or pack?
Tell us how much you need and when — drums, IBCs, sacks or a one-off bulk lot. We'll manufacture or source it and come back with a price.
Prices exclude VAT/sales tax and shipping.
Specifications
| Property | Value |
|---|---|
| Appearance | White needle crystal |
| Assay (Titration) | ≥ 98.0% |
| Water (KF) | ≤ 4.0% |
| Identification (IR) | Conforms to reference |
| Free sulphuric acid | ≤ 0.3% |
Storage & handling
| Property | Value |
|---|---|
| Storage Temperature | Ambient |
| Transport Class | 8 |
| Packing Group | III |
| Acidity | Acid |
Literature values
Published physical properties of the substance, not batch specifications.
| Property | Value |
|---|---|
| Appearance | Monoclinic leaflets or prisms |
| Melting Point | 106-107 °C |
| Boiling Point | 140 °C at 20 mmHg |
| Density | 1.24 (relative, water = 1) |
| Vapour Pressure | 0.0000027 mmHg |
| pKa | pKa = -1.34 |
Source: PubChem CID 6101 (HSDB, ICSC, Haz-Map)
Identification
| Property | Value |
|---|---|
| SKU | 90018846 |
| CAS Number | 104-15-4 |
| IUPAC Name | 4-methylbenzenesulfonic acid |
| EC Number | 203-180-0 |
| Molecular Formula | CH3C6H4SO3H |
| Molecular Weight | 172.20 |
| Exact Mass | 172.0194 |
| SMILES | CC1=CC=C(C=C1)S(=O)(=O)O |
| InChIKey | JOXIMZWYDAKGHI-UHFFFAOYSA-N |
| InChI | InChI=1S/C7H8O3S/c1-6-2-4-7(5-3-6)11(8,9)10/h2-5H,1H3,(H,8,9,10) |
| PubChem CID | 6101 |
| UN Number | UN2585 |
| REACH Code | Y110 |
| TSCA Listed | Yes |
| HTS Code | 29041037 |
| Tariff Code | 2904100090 |
Safety & GHS
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Corrosive
GHS05
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Health Hazard
GHS07
Hazard statements
- H290 May be corrosive to metals
- H302 Harmful if swallowed
- H314 (sub cat. 1C) Causes severe skin burns and eye damage
- H335 May cause respiratory irritation
Precautionary statements
- P260 Do not breathe dust/fume/gas/mist/vapours/spray
- P280 Wear protective gloves/protective clothing/eye protection/face protection
- P301+312 IF SWALLOWED: Call a POISON CENTER or doctor/physician if you feel unwell
- P303+361 IF ON SKIN (or hair): Remove immediately all contaminated clothing. Rinse with water/shower
- P305+351+338 IF IN EYES: Rinse with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing
Documents
Safety Data Sheets (SDS)
Available in English, French, German, Italian, Portuguese, Spanish.
Certificate of Analysis (CoA) by batch
Enter a lot or batch number to retrieve the CoA for that specific batch. We can generate one from spec data if no PDF is on file.
Quality certificates
Molekula Group is certified to ISO 9001:2015 (quality) and ISO 14001:2015 (environmental management), audited by a UKAS-accredited body. Both certificates are valid to 17 May 2028.
Synonyms
- 4-Methylbenzenesulfonic acid
- 4-Toluenesulfonic acid
- Benzenesulfonic acid, 4-methyl-
- p-Methylbenzenesulfonic acid
- p-Toluenesulphonic acid
- p-Tolylsulfonic acid
- Toluene-4-sulfonic acid
- Toluenesulfonic acid
- Tosic acid
- Tosylic acid
Frequently asked questions
What is p-Toluenesulfonic acid commonly used for?
p-Toluenesulfonic acid is widely used as a catalyst in organic synthesis (e.g., esterification, polymerization), a pH regulator in pharmaceuticals, and an intermediate in dye and detergent production.
What is the chemical formula and molecular weight of p-Toluenesulfonic acid?
The formula is CH₃C₆H₄SO₃H, and the molecular weight is 172.20 g/mol.
How should p-Toluenesulfonic acid be stored?
Store at ambient temperature in a tightly sealed container, away from moisture and incompatible substances.
What grades of p-Toluenesulfonic acid does Molekula supply?
Molekula supplies technical grade and ACS reagent grade p-Toluenesulfonic acid, with purity specifications available upon request.
Can Molekula supply p-Toluenesulfonic acid in bulk quantities?
Yes, we offer bulk packaging options (e.g., 25 kg drums, 1 MT totes) for industrial and large-scale applications—contact us for custom solutions.
What documentation comes with an order of p-Toluenesulfonic acid?
Each order includes a Certificate of Analysis (CoA), Material Safety Data Sheet (MSDS), and batch-specific documentation for traceability.
Ready to order or need a custom pack?
Tell us the product, grade, and quantity — Molekula usually responds within one working day with pricing and lead time.